MASS MEASUREMENT OF ⁴⁵ Cr AND ITS IMPACT ON THE Ca-Sc CYCLE IN X-RAY BURSTS

Abstract

Masses of neutron-deficient ⁵⁸Ni projectile fragments have been measured at the HIRFL-CSR facility in Lanzhou, China employing the isochronous mass spectrometry technique. Masses of a series of short-lived T_z = –3/2 nuclides including the ⁴⁵Cr nucleus have been measured with a relative uncertainty of about 10^–6-10^–7. The new ⁴⁵Cr mass turned out to be essential for modeling the astrophysical rp-process. In particular, we find that the formation of the predicted Ca-Sc cycle in X-ray bursts can be excluded